Electric terminal connector



Aug. 25, 1953 F. S. LAMB ETAL ELECTRIC TERMINAL CONNECTOR Filed Dec. 26, 1951 Invervlrors: Fredrick 5. Lamb. Herman E. Hermahson Their A i t'br'nen Patented Aug. 25, 1953 UNITED STATES PATENT OFFICE ELECTRIC TERMINAL CONNECTOR Fredrick S. Lamb, Cleveland Heights, and Herman E. Hermanson, signors to General E ration of New York East Cleveland, Ohio, Illectric Company, acorpo- Application December 26,1951, Serial No. 263,455

connector construction disclosed and claimed in.

co-pending U. S. applicationSerial No. 136,549, F. S. Lamb, filed January 3, 1950, now Patent No. 2,627,048 and assigned to the assignee of the present application.

It is an object of our invention to provide a prong-type electric terminal connector of easily 9 Claims. (Cl. 339145) assembled. construction and having wire-type 7 contact prongs rigidly fixed in place 7 and mechanically connected to the current-supply wires of the electric lamp, cord or other device to which it is attached.

Another object of our invention is to provide an electric terminal connector having wire-type contact prongs which may be firmly mounted in place on the insulator member of the connector body and electrically connected to the current supply conductors of the connector by a simple push-in movement of the prongs into respective prong-receiving recesses in the insulator member.

In accordance with the invention, an electric terminal connector, such as a lamp base or elec-- tric cord plug, is provided with projecting contact prongs or blades each formed of a length of relatively stifl or rigid wire doubled back upon itself into U-shape and locked in place in recesses provided in an insulative end wall of the connector bodv, the inner ends of the prong legs being bent laterally to form transversely extending bent inner end portions between which the insulative.

wall is locked to thereby longitudinally fix the prongs in place on the wall. According to a further aspect of the invention, the insulative wall is formed with a slot therethrough and a groove in its outer face separated from each other and ot a width to snugly receive the respective prong legs and their lateral bent end portions, the slot and groove being disposed at an angle relative to each other of slightly different degree from that of the prong bent end portions whereby the latter I are insertable thereinto only upon spring distortion thereof so as to cause the innermost one of the bent end portions to spring back over the inner side of the insulative wall upon insertion completely through the slot, thereby locking the prong in place in the wall against outward withdrawal therefrom,

the base according to the invention, with theprongs thereof diagrammatically shown in dashdot lines in assembled position thereon; Fig. 3 is afragmentary perspective view of the outer end of the base with the current supply wires omitted; Fig. 4 is an end view of the outer end of the base with the prong legs shown in section; Fig, 5 is a sectional view on the line 5--5 of Fig. 2; and Fig. 6 is a perspective view of one 01 the prongs.

While the invention is shown in the drawing as embodied in a base for an electric incandescent lamp, it will be obvious that it may be applied as well to bases for electric glow lamps or other dischargedevices, or to a terminal connector or attachment plug cap for electric cords and the like.

Referring to the drawing, the lamp there shown comprises a hermetically sealed glass envelope or bulb I having a re-entrant stem 2 provided with a press or seal portion 3 through which are sealed a pair of lead-in or current supply wires 4, 4. Disposed within the bulb l is a light source comprising a tungsten filament 5 electrically connected at its ends to the lead-in wires 4 and supported in position within the bulb by a plurality of support wires 6 anchored in a glass: arbor 1 extending inwardly of the bulb from the stem press 3. The bulb I is exhausted and, if desired, filled with a suitable gas through an exhaust tube 8 communicating with the interior of the bulb, which tube'is afterwards sealed or tipped-01f, as indicated at 9, to hermetically seal the bulb.

Suitably'secured to the neck end ofthe bulb l, as by basing cement III for instance, is an electric terminal connector or base I I according to the invention and comprising a cylindrical metal shell portion l2 suitably secured to an insulative end wall portion I 3 which may be made of any suitable insulative material such as glass, porcelain. molded plastic, or the like. Projecting endwise from the end wall l3 and securely fastened thereto is a pair 01' contact prongs l4, H. In accordance with the invention, the said prongs l4 are'formed of relatively stifi or rigid wire such as, for example, round wire of around .060 inch diameter, preferably made of phosphor bronze, spring brass or other good electrically conductive material.

As shown in Fig. 2, each prong I4 is formed of a length of wire which is doubled back upon itself or looped into a U-shape to form two separated and approximately parallel leg portions I5, I6 joined by a curved outer end or bight portion II. The prongs I4 are securely fastened to the base end wall I3 with their curved ends I! outward. For this purpose the inner ends of the prong legs I5, I6 are bent sidewardly to form laterally bent inner ends or feet portions I8 and I8, respectively, which extend transversely relative to each other and interlock with the wall I3 to firmly anchor the prongs thereto. The bent end I8 of prong leg I is formed by doubling back the inner end portion of the prong leg into the shape of an open hook to thereby provide an outwardly facing shoulder 20 formed by the inner end extremity of the prong leg I5. The bent end I9 of prong leg I6 consists of a lateral portion 2| which is preferably bent back toward the outer end of the prong at an acute angle relative to the prong leg I6 of, for example, around 45 to 55, and an offset inner end or tail portion 22 extending inwardly from the lateral portion 2i in a direction parallel to the prong leg I6. As shown, the bent irmer ends I8, I9 of each prong I4 extend outwardly away from each other to the same side of and angularly to the plane of the two legs I5, I6 of the prong, the bent end I8 preferably extending at a slight angle of, for example, around 30 or so to the plane of the two prong legs I5, I6 and the bent end I9 preferably extending at an appreciable angle of, for example, around 60 or so to the said plane. As a result, the two bent ends I8, I9 of each prong extend transversely relative to each other at an angle of around 90 or thereabouts, as viewed from the end of the prong.

The insulative wall I3 is provided with separate prong-receiving recesses ior the legs I5, I6 of each prong in the form of a slot 23 and a groove 24 in the outer face 25 of the wall I3. The slot 23 is adapted to receive the hook-shaped bent end I8 of prong leg I5 while the groove 24 is adapted to receive the bent end I9 of the other prong leg IS, the slot and groove bein arranged for such purpose at an anglerelative to each. other more or less corresponding to the angularity of the bent end portions I8, I9 of the prong legs. The slot 23 is of a width to snugly receive the prong leg I5 therein 50 as to firmly hold the latter in place in the wall I3 against movement transversely of the slot. Likewise, the groove 24 is formed of a width at its far end (i. e., the end furthest from the slot 23) to snugly receive the tail portion 22 so as to firmly hold the prong leg IS in place in the wall I3 against movement transversely of the groove 24. Additional support to this end is afforded by providing an aperture 26 in the wall I3 in communication with the far end of the groove 24 and which snugly receives the offset tail end 22 of the prong leg I6. Since the slot 23 and groove 24 extend transversely to each other, the snug sliding fit of the Prong leg I5 and bent end I9, respectively, in the slot 23, and in the groove 24 and aperture 26, serves to firmly hold the two legs I5, I6 of the prong in a rigid manner against transverse movement in all directions.

To look the prongs I4 in their respective prongreceiving slots 23 and grooves 24 against withdrawal therefrom, means are provided to cause the innermost bent end I8 of the prong to automatically snap or spring over and engage with the inner side 21 of the wall I3 PO passage of the said bent end I8 completely through the slot 23. For this punpose, the slot 23 and groove 24 are arranged at an angle relative to each other slightly different (preferably around 10 or so greater) than that of the bent ends I8, I9 of the prong so as to require the bent ends I8, I9 to be angularly twisted or spring-distorted out of their normal angular position in order to permit their insertion into the slot 23 and groove 24. Thus; when the-bent end I8 clears or passes beyond the inner side 21 of the wall I3 during the insertion of the prong I4 into its respective slot 23 and groove 24, the said bent end I8 then springs back to its normal unfiexed position relative to the other bent end I9 thus swinging its outwardly facing shoulder extremity 20 into a position over the inner side 21 of wall I3 (as shown in Fig. 4) where it engages therewith to lock the prong against outward withdrawal from the slots 23 and groove 24. At the same time the lateral extending portion 2| of the bent end I9 of the other prong leg I6 engageswith the bottom 28 of the groove 24 to limit the inward movement of the prong into the slot 23 and groove 24, the longitudinal spacing of the opposed outwardly and inwardly facing shoulders 20 and 2I being just sufiicient to snugly receive the wall I3 therebetween so as to effectively lock the prong in place on the wall against longitudinal movement.

The lead-in or current supply wires 4, 4 of the lamp are mechanically connected to the respective prongs I4 in the manner shown'in Fig. 5. For this purpose, the wall I3 is provided with an aperture 29 communicating with the near end of the groove 24 (i. e., the end nearest the slot 23) and in alignment with the prong leg I6 when in place in the groove 24. The lead-in wire .4 is threaded through the aperture 29 at the time the base II is placed over the neck end of the bulb I in position for cementing or fastening thereto and before the prongs I4 have been inserted in the prong-receiving recesses in the wall I3. To facilitate such insertion of the wires 4 into the apertures 29, the latter are flared out toward the inner side 21 of the wall I3, as indicated at 30.

.With the base II mounted in place on the bulb I, the portion of the lead-in wire 4 projecting outwardly beyond the wall I3 is then bentback over the outer side 25 of the wall I3 and back into the slot 23, with the exposed portion 3I of the wire 4 received within a groove 32 which is preferably provided in the outer side 25 of the wall I3 whereby the said exposed wire portion 3| is located flush with the outer side 25 of the wall so as to be protected therewithin. Upon subsequent insertion of the prong legs I5, I6 into the slot 23 and groove 24, the portions of the wire 4 located within the groove 24 and the slot 23 are trapped and tightly wedged or clamped between the walls of the said groove and slot and the respective prong legs I5, I6 therein as shown in Fig. 4, thus mechanically connecting the prong I4 to the lead-in wire 4 and providing a good electrical connection therebetween. At the same time the prong leg I 6 is itself, in turn, wedged tight against the wall of the widened end of the groove 24 by the portion of the lead-in 4 therein so as to further aid in supporting the prong leg I6 rigidly in the wall I3. To accommodate both the lead-in wire 4 as well as the prong leg I6 so as to permit insertion of the latter thereinto, the groove 24 is tapered or widened out toward its near end to a width approximating that of the combined diameters of the lead-in wire 4 and prong leg I6.

From the above it will be evident that the attachment of the contact prongs It to the base completely through the slot 23 and springs or snaps over the inner side 21 of the base wall 13 whereupon the prongs become automatically locked in place on the said wall. Thus, the base according to the invention can be assembled. and the electrical connections made to the contact prongs thereof, in a simple, easy and quick manner, without the need of any solder operations whatsoever. The snug fit of the prong legs l5, l6 and their bent ends l8, II in the slot 23 and in the groove 24 and aperture 26 serve to rigidly anchor the prongs in place in the wall It against lateral movement or wobbling in all directions, while the snug at of the wall ll between the opposed shoulders 20, 2| of the prongs serves to lock the prongs in place in the wall against longitudinal movement. The separation between the outer legs l5, it of the prongs provides the necvides beveled or rounded outer end surfaces on the prongs which therefore serve to facilitate insertion of the prongs between as well as removal from the spring contacts of the socket or receptacle.

Although a preferred embodiment of our invention has been disclosed, it will be understood that th invention is not to be limited to the speciflc construction and arrangement of parts shown, but that they may be widely modified within the spirit and scope of our invention as defined by the appended claims.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. An electrical connector comprising a body member provided with an insulative wall, and a contact prong formed of rigid wire bent into U-shape and securely fastened to said wall with its U-bend outward, the two legs of the prong having laterally bent inner end portions and said wall having a slot therethrough and a groove in its outer face separated from each other and of a width to snugly receive the respective prong legs and their said bent end portions, said slot and groove being disposed at an angle relative to each other of slightly different degree from that of the prong bent end portions whereby the latter are insertable thereinto only upon springdistorti n thereof, and said bent end portions being separated longitudinally of the prong a distance to snugly receive the said wall therebetween to thereby lock the prong longitudinally in place upon insertion of the innermost one of said bent end portions completely through the said slot.

2. An electrical connector comprising a body member provided with an insulative wall, and a contact prong formed of rigid wire bent into U-shape and securely fastened to said wall with its U-bend outward, the two legs of the prong having laterally bent inner end portions extending transversely relative to each other and said wall having a slot therethrough and a groove in its outer face separated from each other and of a width to snugly receive the respective prong legs and their said bent end portions, said slot and groove being disposed at an angle relative to each other of slightly diii'erent degree from that of the prong bent end portions whereby the latter are insertable thereinto only upon spring-distortion thereof, and said bent end portions being separated longitudinally of the prong a distance to snugly receive the said wall therebetween to thereby lock the prong longitudinally in place upon insertion of the innermost one of said bent end portions completely through the said slot, at least a portion of the outermost one of said bent end portions extending in the general direction of the length of and in a sociated prong leg.

3. An electrical connector as set forth in claim 2 wherein the outermost one of the prong bent end portions is bent back at an acute angle to the associated prong leg and is provided with an inwardly extending offset end parallel to the associated prong leg, said wall portion having an aperture therethrough communicating with said groove and snugly receiving the said inwardly extending offset end of the outermost bent end portion of said prong.

4. An electrical connector as set forth in claim 3 wherein the inner end of one of said prong legs is doubled back upon itself to form the innermcst one of said bent inner end portions.

5. Anelectrical device having a terminal connector comprising a body member provided with an insulative wall, a contact prong formed of rigid wire bent into U-shape and securely fasplane including theastened to said wall with its U-bend outward, the

two legs of the prong having laterally bent inner end portions spaced apart longitudinally of the prong and engaging opposite sides of said wall to lock the prong in place thereon against longitudinal movement, said wall having a slot therethrough and a recess therein snugly receiving portions of respective ones of said prong legs to firmly support the prong in place in said wall against transverse movement in planes at approximately right angles to each other, the bent inner end portion of one of said prong legs being insertable through said slot from one to the other side of said wall, said wall further having an aperture therethrough communicating with the said recess, and a current conductor extending outwardly through said aperture and said recess and wedged in the said recess by the prong leg therein to thereby electrically connect the prong to said conductor.

6. An electrical device having a terminal connector comprising a body member provided with an insulative wall, a contact prong formed of rigid wire bent into U-shape and securely fastened to said wall with its U-bend outward, the two legs of the prong having laterally bent inner end portions spaced apart longitudinally of the prong and extending transversely relative to each other and said wall having a slot therethrough and a groove in its outer face separated from each other and of a width to snugly receive at least a portion of the respective prong legs, said slot and groove being disposed at an angle relative to each other of slightly different degree from that of the prong bent end portions whereby the latter are insertable thereinto only upon spring-distortion thereof, and said wall being said wall further having an aperture there- .through communicating with said groove and portion having a pair of contact prongs formed of rigid wire bent into U-shape and securely fastened to said wall with their U-bends outward, the legs of each prong being provided with lateral inner end portions extending transversely relative to each other and the said wall having grooves in its outer face for snugly receiving at least a portion of on of the lateral end portions of respective prongs and slots therethrough for passage of the other lateral end portion of respective prongs andadapted to snugly receive the associated prong leg, the groove and slot for each prong extending at an angle relative to each other of slightly different degree from that of said lateral prong end portions whereby th latter are insertable into the said groove and slot only upon spring-distortion thereof, said insulative wall having apertures therethrough com municating with respective ones of said grooves and said wall being snugly locked between the said lateral prong end portions of the prongs to longitudinally fix them in place on said wall, and said current conductors extending through said apertures into respective ones of said grooves and being tightly wedged in the said grooves by the respective prong legs therein to thereby elec- 8. A contact prong for a lamp base or similar 7 device, said prong comprising a length of rigid wire bent into U-shape to form two separated side-by-side leg portions having laterally bent free end portions located at different distances from the closed end of the prong to form longitudinally spaced shoulders thereon, said bent end portions extending laterally outward from the respective prong legs in transverse relation to each other.

9. A contact prong for a lamp base or similar device, said prong comprising a length of rigid wire bent into U-shape to form two separated side-by-side leg portions, the free end of one of said prong legs being bent back upon itself to the outward side of the prong leg to form an open hook end having its end extremity facing toward the closed end of the prong, and the free end of the trically connect the said conductors to respective prongs.

other prong leg being bent back upon itself at a point nearer the closed end of the prong than the end extremity of said hook end and extending in a direction to the outward side of and at an acute angle to the prong leg and transverse to the said hook end to form an angular bent end, said angular bent end having its free end bent back in the direction of the open end of the prong and parallel to the prong leg to form a laterally offset portion thereon.

FREDRICK S. LAMB. HERMAN E. HERMAN-SON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,033,748 Wallace Mar. 10, 1936 2,559,988 Noyes July 10, 1951 FOREIGN PATENTS Number Country Date 618,961 France Dec. 23, 1926 

